1. Field of the Invention
The present invention is related to a storage device for storing semiconductor components or reticles, and more particularly, to a reticle pod having the function of gas exchange in the pellicle film.
2. Description of the Prior Art
In the rapidly developing modern semiconductor technology, optical lithography tool plays an important role. The pattern definition relies fully on optical lithography technology. In the application of optical lithography tool related to semiconductors, pre-designed circuit paths are fabricated as light-transparent reticle in specific form. Basing on the principle of exposure, after light from the light source passes through the reticle and is projected on a silicon wafer, specific circuit pattern can be exposed on the silicon wafer. However, since any kind of dust (such as particles, powders, and organic matters) adhering to the reticle can cause degradation of the quality of the projected pattern, the reticle used to produce pattern on silicon wafers is required to be kept absolutely clean, and the silicon wafers or other semiconductor components on which pattern is to be produced also have to be kept absolutely clean. Therefore in ordinary wafer processes, clean rooms are provided for preventing from contamination caused by particles in the air. However, the status of absolute dustless is still inaccessible in clean rooms at present.
Thus, in modern semiconductor processes, contamination-resistant reticle pods are employed for storing and transporting reticles to maintain the cleanliness of reticles; and contamination-resistant semiconductor storage device are also employed for storing and transporting semiconductor components to maintain the cleanliness of semiconductor components. The reticle pods are used to store reticles in semiconductor process to facilitate carrying and transporting of reticles between platforms and to isolate the reticles from air for preventing from contamination of reticles caused by impurities and thus leading to changes; the semiconductor storage devices are used to store semiconductor components in semiconductor process to facilitate carrying and transporting of semiconductor components between platforms and to isolate the semiconductor components from air for preventing from contamination of semiconductor components caused by impurities and thus leading to changes. Therefore, in advanced semiconductor Fabs, the cleanliness of reticle pods and semiconductor storage devices is required to comply with SMIF, i.e. the cleanliness is maintained below Class 1.
A reticle pod of conventional art, as shown in FIG. 7, usually comprises a shell a, on which are disposed with multiple supporting components c for sustaining reticle d. The supporting components c can sustain the lower surface of reticle d and restrict the two edges of the reticle, and the supporting components c can be rested on by the reticle for securing the reticle. A base b opposite to the shell a, which covers and joins with the shell a to form a space for storing reticle d. Meantime, gas is filled into the storage device of reticle d to maintain the cleanliness.
However, in order to further increase the yield of products and reduce the cost of production, not only is the standard of cleanliness to be complied to, but the problem of pollution of reticles caused by external gas is also to be overcome. The sources of external gas include, in addition to air, outgas released by the storage device itself which is made of polymer material and volatile gas generated from residue of trace amount of chemical solution on reticles or semiconductor components. These unexpected gases will cause haze on the surface of reticles or semiconductor components, which will then make reticles or semiconductor components defective and discardable and lead to increase of production cost. It is thus an important issue to explore how to solve the problem of reticle haze by filling in gas in reticle pods of prior art. Taking the aforementioned concern into consideration, the present invention provides a reticle pod having the function of gas exchange in pellicle film.